MONTGOMERY, Ala. (AP) — The head of the Southern Poverty Law Center on Friday announced that he is stepping down, the latest high-profile departure from the watchdog organization best known for its work monitoring extremist groups.

Southern Poverty Law Center President Richard Cohen sent an email to staff saying that he would be stepping down from his leadership role at the organization. The organization last week fired founder and prominent civil rights attorney Morris Dees for unspecified reasons.

“Whatever problems exist at the SPLC happened on my watch, so I take responsibility for them,” Cohen wrote.

Cohen in October had approached the organization’s board about finding a “new generation” of leadership. He wrote Friday that he was stepping up that timeframe in light of recent events, and asked the organization’s board to immediately begin the search for an interim president “in order to give the organization the best chance to heal.”

He also asked his staff for patience as they bring in an outside party to review the organization’s workplace environment.

The SPLC did not elaborate on the reasons behind Dees’ termination. In a statement about Dees’ departure, Cohen only said the organization is “committed to ensuring that the conduct of our staff reflects the mission of the organization and the values we hope to instill in the world.”

The group this week announced it hired Tina Tchen, a one-time aide to former first lady Michelle Obama, to review its workplace. Tchen was chief of staff to the former first lady and now works for a Chicago law firm focusing on workplace issues including gender and racial equity and sexual harassment.

Cohen asked SPLC staff to let the “process play out before jumping to conclusions.”

“We’re going through a difficult period right now, and I know that we’ll emerge stronger at the end of the process that we’ve launched with Tina Tchen,” Cohen wrote.

Dees founded the Montgomery-based law center with a partner in 1971 as a watchdog for minorities and the underprivileged. A decade later he won a $7 million judgment against the United Klans of America on behalf of Beulah Mae Donald, whose son was murdered by KKK members in Mobile.

The organization has sometimes been criticized for its aggressive fundraising tactics. In 2017, tax records show, the organization had some $450 million in assets.

Last year, it agreed to pay a $3.4 million settlement after wrongly labeling a British organization and its founder as extremists.